Hot-air furnace and ventilating system



i Sept. 10, 1929.

c. A. FREE 1,72 7,540

HOT AIR FURNACE AND VENTILATING SYSTEM Filed Nov. 26, 1926 i-F1a. 1

Patented Sept. 110, 1929. C

UNITED STATES 'CHESTER A. FREE, OF ATTICA, INDIANA.

HOT-AIR ,FURNACE -AND VENTILATING SYSTEM.

vApplication led November 26, 1926. Serial No. 150,672.

This invention relates to a hot air furnacel and Ventilating system.

The chief object of the invention is to equip a hot air furnace with means and controls therefor, whereby the same will supply relatively pure air to the rooms to be heated.

The chief feature ofthe invention consists in providing a bypass control arrangement between the cold air return and smoke pipe or chimney, and arrangin .the same so ,that a portion of the returne air is by--passed to the smoke pipe and a similar amount is Ysupplied fromwithout the building heated.

Another featureyof the invention consists in by-passing a portionof the impure returned air through the lire for draft and closing the previously indicated by-pass so that y,the draft will not be impaired or in by-pas'sing a portion each way if desired.

The full nature of the inventionwill be understood from the accompanying drawings and the following description and claims:

In the drawings Fig. 1 illustrates a heating system for a building, the furnace being partly shown in elevation and partly in section,

and the several conduits being similarly illustrated. Fig. 2 is an enlarged central sectional view of a portion of the lfire bowl.

In the drawings 10 lindicates a casing of a furnace having a header or top 11 from which extend .the usual hot air pipes 12 that discharge into the outlets 13 usually provided with registers'14. The building is also provided with a cold air register or intake 15, which is connected by the cold air duct or return pipe 16 to said casing 1,0 near the lbottom thereof and a boot .or settling chamber 17 to which reference will be hadlater. The intake 18 which connects the cold yair register opening with at least one return pipe 16, has another opening 19 and a cold air register or control 20 is associated therewith for supplying fresh air from without the building to the return pipe 16. The 4furnace is also provided with a smoke pipe 21 having the usual check damper 22 controlled by chain 23 which is also connected to the draft damper 24 carried by the ash pit door 25. The furnace has the usual fire door 26.4 The heating head 27 discharging through radiator 127 by wayof conarrangement above the ash pit and the same includes an annular channel 35 with a plurality of ports 36 that discharge inwardly beneath and below the level 0f the grate. A

conduit 37 extends from said member 34 and f beyond the furnace casing 10. The casing 32 includes a plurality of vertical passages 132 which-communicate at their lower ends with channel 35 by ports 135 and at their upper ends with an annular channel 133 in said casing. Said channel 133 discharges air inwardly above the fire brick or bowl 29 through ports 136, see Fig. 2.

The boot 17 includes a depending baffle or partition 38 and an adjacent outlet 39 connected bya by-pass 40 to the smoke pipe and' the cross sectional area -of this by-pass is .at least equal to that of the fresh air intake 20. The capacity of boot 17is at least equal to and preferably greater than that of the pipe or pipes entering or leaving the same respectivelyrso that the air therein has a decreased velocity and the baille 38 therein tends to separate t e air into hot and cold layers orcomponents. The opening 39 is so positioned with respect to baille 38 in the boot that the air bypassed through conduit 40 is the warmer return air. When intake 20 is employed substantially none of this pure airis thus bypassed.

The branch 37 of conduit 40 and the con# nection of the conduit 40 to the smoke pipe also will be opened, thereby insuring that the air always will be purified by reason of the removal of a portion of the air from the boot 17 and opening 39 and replacement through the intake `20. The air in conduit 37 passes through the grate 31 from ports 36, thereby assisting the draft. Also a part of the air is discharged into the flames above the fire pot thereby securing complete-combustion when the fire is under increased draft. When the re is to be checked, draft damper 24 is closed and the draft by-pass 37 is cut oif by valve 42. If the valves are connected as indicated, j and the damper 22 is opened the Vsmoke pipe receives part of its draft from conduit440 and the cold air return as aforesaid. It is desirable at times not to connect chain 23 with chain 43 for simultaneous operationand iii that event the chain 43 is operated independently and the valve 42 is then the full equivalent of what is normally called-the inter- Y mediate check damper.

When it is desired to operate the dual valve 42' independently ofcliain 23, it may beassumed that draft-and check dampers 24 and 22 respectively, are closed, that is, the furnace is in neutral control. Elevation of chain 43 then closes by-pass 40 and opens by-pass 37 to the boot 17 Thus, substantially all the draft for the furnace is taken through yopening 39. kLowering or reverse movement of chain 43 closes by-pass 37 and opens by-pass 40 and practically the entire pull of thechimney is then drawing off the heated and thererlthrough the lire as draft, or out through thevv fore less pure air from boot 17 through opening 39. In either event the less pure return air is being continuallydisposed of either smoke pipe. Fresh air, therefore, supplied through inlet 2O is being constantly introduced to the heating system in a like amount and this air passes into chamber 45 for subsequent heating. f

While the invention is herein illustrated as applied to a pipe type of furnace, it will be readily understood that the same also can be Vreadily adapted to a pipeless type of furnace,

l the piping being suitably modified for such purpose, and likewise while the hot air furnace is shown as of the coal or w'ood type, 1t

can be of any type for heatin@ the air, andv in f certain instances it may be oi? a simpler type wherein aV part of the returned air is not passed for assisting in the draft or increasing the heating effect.

The furnace herein illustrated is also shown provided with a chamber 45 beneath the ashY pit and with which the entire air heating chamber ofthe furnace is in direct communication. Thus, the colder' air received through the intake 2O passes beneath the fur-k nace and abstracts the heat from the ash' pit before passing upwardly and around the fire heating conduits. v

The invention claimed is: f 1. The combination with a. hot air furnace y bowl andl over the flame shell into the several v e having an `air-heating chamber and a smoke pipe; of an air return communicating with the ash pit and the air heating chamber of said.V furnace, a by-pass between said return baffle is bypassed to the and said smoke pipe, a-second by-pass establishing communication between the first bypass and the fire pot of said furnace, and valve means controlling said by-passes.

2. The combination with a hot air furnace having an air heating chamber and a smoke pipe; ofean 'air return communicating with 1 the ashl pit and the air heating chamber of said furnace, a by-pass communicating at one end with the upper part of said air return near its juncture with said ash pit and with said smoke pipeIl at its other end, a second bypass communicating at one end with said first by-pass and atitsother end with the fire pot of said furnace, and a single valve selectively controlling the lmoke pipe andiiie potcommunication witli the first by-pass.l

. 3. The combination with a hot air furnace having a smoke pipe and an air heating chamber; ofahorizontally disposed boot at the base of said furnace and communicating with the heating chamber and the ash pit thereof, a baffle in said boot closing the upper part of said boot at its inner end, a return pipe communicating with the outer end ofsaid boot, a by-pass `establishing communication between the upper portion of' said boot and said smoke pipe,a second `by-pass'establishing communication between said first by-pass -and the fire pot of said furnace, and valve means controlling said Yby-'passes 4. In a vheating system the combination of a furnace having acheck damper, a draft damper, means connecting the same for simultaneous operation, a smoke pipe and a fire pot, an airreturn connected to the furnace for recirculation, a branched conduit connected at one end to the return'and at its other end to the smoke pipe and to the fire pot, valve means-simultaneously and selectively controlling the communication of said ranged so that the foul air trapped by the baflie is bypassed to the pit.

6. In a hot air furnace the combination of an air heating chamber, an ash pit, a smoke pipe, a-horizontally disposedl boot, a bypass therefrom having communication with the ash pit, a 'baille interposed between the boot and the heating chamber communication, and

arranged so that the foul air trapped `by the pit, a second bypass connected to the first bypass and connected to the smoke'pipe, and valve means proportionately controlling the division of air through the bypass directly to the smoke pipe or indirectly thereto through the ash pit.

7. A hot air heating system including in combination a cold air return register for receiving air from the building to be heated, a hot air furnace having a smoke pipe, anair heatin chamber, a horizontally disposed boot at the ase of said furnace and communicating with the heating chamber directly and the ash pit thereof indirectly, a baiie in said boot closing the upper part of said boot at its inner end, a return pipe communicating at one l end with the outer end of the boot, and at its opposite end With the register, a by-pass establishing communicationfbetween the upper portion of said boot and said smoke pipe, a second by-pass establishing communication between said first by-pass and the fire pot of said furnace, valve means controllin said f by-passes, and a cold and fresh air lntake communicating with said return pipe adjacent the cold air register.

In Witness whereof, I have hereunto aiixed my signature.

CIFlESTER A. FREIE. 

